• Basic validation is to ensure that the activity has all the necessary information to be completed.

• All pending service histories must be completed when completing the activity (mandatory).

• Required service histories must be entered for worked assets.

• For each asset that worked, loop through the list of required service history types defined on the activity.

• Find all service histories in the list of activity service histories that its service history type = current service history type being processed and either asset ID = empty or equal current asset being processed.

• If not found, issue an error that “A service history of type %1 is missing for asset %2”.